A significant proportion of young adults drink heavily and consequently are at risk for a variety of problems such as alcohol-related motor vehicle crashes, injury, and behavioral and academic problems. The objective of this research is to investigate ways to effectively reduce harmful drinking in college students who have been identified by college authorities as having had an alcohol-related incident. Whereas mandated alcohol education or treatment for alcohol violations on college campuses is ubiquitous, the efficacy of such interventions has not been studied. Motivational approaches with hazardous drinking college students have shown promise. Thus, a motivation-based intervention designed for those who are required to attend alcohol counseling may prove efficacious. Intensifying the intervention by adding a booster session might further enhance efficacy. Additionally, the common association between alcohol and sexual activity among young adults suggests that including risky sexual behavior as an avoidable alcohol-related problem could be successful as well. In this proposed randomized trial, a 2 (Motivational Interview vs. Standard Education) X 2 (2-week booster vs. none) factorial design will be used to determine whether MI and a booster session separately, and in conjunction, are effective in reducing alcohol-related consequences and alcohol use in college students mandated to an alcohol intervention following an alcohol-related emergency or infraction. The Standard Education condition will be based on college standards for alcohol education. Subjects will be followed at 3 and 12 months after the baseline intervention. Primary outcome variables include alcohol consumption, and alcohol-related injuries and consequences including unprotected sexual behavior. It is hypothesized that: 1) groups receiving MI will show the lowest levels of heavy drinking and alcohol problems, with the groups receiving MI plus booster showing the greatest effect, and that 2) intervention effects will be mediated by alcohol expectancies, stage of change, use of behavioral alcohol-reduction strategies, and treatment seeking. This study will extend previous research by evaluating the use of MI with individuals who are mandated to treatment, by including a booster session, and by expanding the focus to include alcohol-related sexual risk behavior. The development of effective interventions for young adults who are engaging in harmful drinking should reduce the chronicity of alcohol-related problems and injuries in this population.